idnits 2.17.1 draft-ietf-mip4-nemov4-dynamic-06.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (February 23, 2012) is 4439 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) No issues found here. Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group G. Tsirtsis 3 Internet-Draft V. Park 4 Intended status: Standards Track V. Narayanan 5 Expires: August 26, 2012 Qualcomm 6 K. Leung 7 Cisco 8 February 23, 2012 10 Dynamic Prefix Allocation for NEMOv4 11 draft-ietf-mip4-nemov4-dynamic-06.txt 13 Abstract 15 The base NEMOv4 specification defines extensions to Mobile IPv4 for 16 mobile networks. This specification defines a dynamic prefix 17 allocation mechanism. 19 Status of this Memo 21 This Internet-Draft is submitted to IETF in full conformance with the 22 provisions of BCP 78 and BCP 79. 24 Internet-Drafts are working documents of the Internet Engineering 25 Task Force (IETF). Note that other groups may also distribute 26 working documents as Internet-Drafts. The list of current Internet- 27 Drafts is at http://datatracker.ietf.org/drafts/current/. 29 Internet-Drafts are draft documents valid for a maximum of six months 30 and may be updated, replaced, or obsoleted by other documents at any 31 time. It is inappropriate to use Internet-Drafts as reference 32 material or to cite them other than as "work in progress." 34 This Internet-Draft will expire on August 26, 2012. 36 Copyright Notice 38 Copyright (c) 2012 IETF Trust and the persons identified as the 39 document authors. All rights reserved. 41 This document is subject to BCP 78 and the IETF Trust's Legal 42 Provisions Relating to IETF Documents 43 (http://trustee.ietf.org/license-info) in effect on the date of 44 publication of this document. Please review these documents 45 carefully, as they describe your rights and restrictions with respect 46 to this document. Code Components extracted from this document must 47 include Simplified BSD License text as described in Section 4.e of 48 the Trust Legal Provisions and are provided without warranty as 49 described in the Simplified BSD License. 51 Table of Contents 53 1. Requirements notation . . . . . . . . . . . . . . . . . . . . 3 54 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 55 3. Dynamic Mobile Prefix allocation . . . . . . . . . . . . . . . 5 56 3.1. Mobile Client Considerations . . . . . . . . . . . . . . . 5 57 3.2. Home Agent Considerations . . . . . . . . . . . . . . . . 5 58 4. Security Considerations . . . . . . . . . . . . . . . . . . . 7 59 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 60 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 61 7. Normative References . . . . . . . . . . . . . . . . . . . . . 10 62 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11 64 1. Requirements notation 66 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 67 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 68 document are to be interpreted as described in [RFC2119]. 70 2. Introduction 72 The base NEMOv4 specification [RFC5177] defines extensions to Mobile 73 IPv4 [RFC5944] for mobile networks. This specification adds support 74 for dynamic allocation of mobile prefixes by the home agent. 76 3. Dynamic Mobile Prefix allocation 78 The following extension is defined according to this specification. 80 3.1. Mobile Client Considerations 82 According to this specification, the Prefix field of the Mobile 83 Network Request Extension MUST be set to zero to indicate that that 84 the Mobile Router requests mobile network prefix(es) to be assigned 85 to it by the home agent. In this case, the Mobile Router MAY set the 86 prefix length field of such extensions to zero or to a length of its 87 choice as a hint to the home agent. According to this specification, 88 mobile network request extensions with the prefix field set to zero 89 MAY be included in a registration request message either during 90 initial registration or during a subsequent registration. 92 When a Mobile Router receives a registration reply it MUST process it 93 as defined in Mobile IPv4 [RFC5944] and [RFC5177]. If one or more 94 network acknowledgement extension are included with the Code field 95 set to "Success" the Mobile Router SHOULD treat the prefixes in the 96 corresponding prefix fields as allocated prefixes and create the 97 appropriate bindings as defined in [RFC5177]. 99 If in response to a registration request with a mobile network 100 request extension with the prefix field set to zero, a Mobile Router 101 receives a registration reply with a network acknowledgement 102 extension including Code field set to 1 "invalid prefix", it may use 103 it as a hint that the home agent does not support dynamic prefix 104 allocation. 106 3.2. Home Agent Considerations 108 A home agent receiving a mobile network request extension with the 109 prefix field set to zero MAY return a mobile network acknowledgement 110 extension [RFC5177] with the prefix field set to the prefix allocated 111 to the Mobile Router. The length of that prefix is at the discretion 112 of the home agent. The home agent MAY take into account the prefix 113 length hint if one is included in the mobile network request 114 extension. Once the home agent allocates a prefix it MUST maintain 115 the prefix registration table as defined in [RFC5177]. Alternatively 116 the home agent MAY return a mobile network acknowledgement extension 117 with the Code field set to one of the negative codes defined in 118 [RFC5177]. 120 Dynamic mobile prefix allocation as defined in this specification MAY 121 be combined with dynamic home address allocation as defined in 122 [RFC5177]. In other words the home address field of the registration 123 request message MAY be set to zero while the message also includes 124 one or more mobile network request extensions with the prefix field 125 also set to zero. 127 Once the home agent allocates a prefix it MUST maintain the prefix 128 registration table as defined in [RFC5177]. The lifetime of the 129 allocated prefix will be equal to the lifetime of the binding cache 130 entry. The Mobile Router may request for multiple mobile network 131 prefixes to be assigned by the home agent. For a Mobile Network 132 Prefix for which the assignment was unsuccessful, the Code field in 133 the corresponding Mobile Network Acknowledgement extension should be 134 set to MOBNET_UNASSIGNED. 136 For dynamic prefix allocation the Mobile Router's home address MAY be 137 used to identify the client if it is not set to zero. Otherwise, as 138 defined in the NAI extension [RFC2794] of Mobile IPv4 [RFC2794], the 139 NAI extension needs to be included in the registration request, in 140 which case the same extension SHOULD be used to identify the Mobile 141 Router for prefix allocation purposes. 143 4. Security Considerations 145 This specification operates in the security constraints and 146 requirements of Mobile IPv4 [RFC5944], NAI [RFC2794] and [RFC5177]. 148 Home agent implementations SHOULD take steps to prevent address 149 exhaustion attacks. One way to limit the effectiveness of such an 150 attack is to limit the number and size of prefixes any one mobile 151 router can be allocated. 153 5. IANA Considerations 155 A new Code Value for the Mobile Network Acknowledgement Extension: 4 156 (Home Agent cannot assign a mobile network prefix - 157 MOBNET_UNASSIGNED). 159 6. Acknowledgements 161 The authors would like to thank Pete McCann, Alexandru Petrescu, 162 Ralph Droms, and Jari Arkko for their reviews and comments. 164 7. Normative References 166 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 167 Requirement Levels", BCP 14, RFC 2119, March 1997. 169 [RFC2794] Calhoun, P. and C. Perkins, "Mobile IP Network Access 170 Identifier Extension for IPv4", RFC 2794, March 2000. 172 [RFC5177] Leung, K., Dommety, G., Narayanan, V., and A. Petrescu, 173 "Network Mobility (NEMO) Extensions for Mobile IPv4", 174 RFC 5177, April 2008. 176 [RFC5944] Perkins, C., "IP Mobility Support for IPv4, Revised", 177 RFC 5944, November 2010. 179 Authors' Addresses 181 George Tsirtsis 182 Qualcomm 184 Email: tsirtsis@googlemail.com 186 Vincent Park 187 Qualcomm 189 Phone: +908-947-7084 190 Email: vpark@qualcomm.com 192 Vidya Narayana 193 Qualcomm 195 Phone: +858-845-2483 196 Email: vidyan@qualcomm.com 198 Kent Leung 199 Cisco 201 Phone: +408-526-5030 202 Email: kleung@cisco.com